I’ve been thinking about this, and I think one of the factors is inter-generational wealth transfer.

If you look, here in the Netherlands, many of the families that made out like bandits in the slave trade and colonial exploitation are still very wealthy and influential. That results in an incentive, baked into the economic tissue of the country, to continue to ignore these topics.

I could be wrong, but my impression is that this is also true for England, but to a (much) higher degree than over here.